Tube rolling mill



4 Sheets-Sheet l M Y) ovion,

w. J. N ORTON TUBE ROLLING MILL.

Filed Dec. 24, 1935 I I I I ll al --L I} w. J. NORTON TUBEJROLLING MILL Filed Dec. 24, 1935 Sept. 29, 1936.

4 Sheets-Sheet 2 Sept. 29, 1936.

w, J. NORTON TUBE ROLLING MILL Fil ed Dec. 24, 192 5 4 Sheets-Sheet 5 Sept. 29, 1936. w. J. NORTON 2,056,110

TUBE ROLLING MILL 4 Sheets-Sheet 4 Filed Dec. 24, 1935 Patented Sept. 29, 1936 TUBE ROLLING MILL William John Norton, Sali'ord, England, assigno. to Sir James Farmer Norton & Company *Limited,'Salford, England, a British company Application December 24, 1935, Serial No. 56,099

In GreatlBritainDecembcr 21, 1934 8 Claims. (CI. 80-14) when the dies or rolls cease to grip the tube, an

increment of feed and .a partial turn being imparted to the tube during each return movement. The object of my present invention is to provide improvements in the said type of mill which facilitate and expedite the production of the reduced tubes.

. In accordance with my invention, the mandrel is reciprocated through a definite path and does 20 not advance through the dies or rolls with the tube being rolled or reduced. The tube alone has the increments of feed and turning movements imparted thereto and is freed from the mandrel at each cycle of operations.

The dies or rolls act to swage the tube during less than 180", preferably not more than 120 of each revolution of the dies and the carriage or slide by which the mandrel and tube are reciprocated is actuated by a crank, connecting rod and a-bell crank lever running in part in a cam track so as to compensate for the varying angularity of the crank and to give to the carriage or slide a rate of movement substantially the same as that resulting from the surfaceengagement of the swages and tube during the swaging stroke. The extension of the tube due to its reduction by the swages results'in an advance through the dies.

The invention therefore comprises the im- 40 proved combinations and arrangements of parts as hereinafter described and claimed.

Referring to the accompanying explanatory drawingsz- Figures 1, 2 and 3 taken together constitute a side elevation of a machine constructed in one convenient form in accordance with this invention.

"Figures 4, 5 and 6 taken together constitute a plan view of the machine shown in Figures 1, 2

Figures 7, 8 and 9 are detailed views of parts included in the remaining figures, which will be hereinafter referred to.v

Figure 10 shows the relative positions of the swaszes and crank.

In Figures 1 and 4, upon the bed a of the machine is mounted for reciprocatory movements a slide 12 (see also Figure 8 which is a sectional view a of the slide) to which is secured the rear 'end of a screw 0, which can be termed the feed screw, and 5 also a chuck or collet d for holding the rear end of a mandrelle. The feed screw 0 isadapted for intermittent rotary movement as hereinafter de scribed and it turns a gear wheel I which meshes with a gear wheel g upon the sleeve h carrying 10 the chuck or collet d. The slide b is reciprocated by the rod 2' to which it-is adjustably secured by nuts on the opposite sides of a lug it upon the slide through which the rod 2' passes.

The screw 0 can be given rotary movements by 15* the electric motor m through the sprocket wheels 12 and a chain. There is an axially fixed ratchet wheel 17 through which the feed screw threads, the said ratchet wheel serving in conjunction with a 'pawl, not shown, to cause the screw to turn in a 20 forward direction when the screw is being propelled forwards, that is towards the swages to be hereinafter referred to, but allowing the screw to move without turning when it is being propelled backwards.

Referring now to Figures 2 and 5, which show the middle section of the machine, the mandrel e passes through the chuck or collet q upon a slide 1' but isnot engaged by such chuck or collet. The latter grips the tube s which is being reduced by the machine; The feed screw 0 threads through a part if in the slide 1' (see Figure 9) which acts as a nut with respect to the screw,'reciprocatory movements of the screw causing corresponding reciprocatory movements of the nut and slide and 5 arotary,movement of the screw imparting an additional movement to the slide along the bed a. A wheel-u in the slide is feather keyedto the screw 0 so that it turns with the latter and such wheel gears with a wheel 1;, which is upon a sleeve. 40 w rigid with the collet q so that rotary movements of the wheel 1; cause rotary movements of the collet or chuck q and the tube 8. I

Referring now-to Figures 3 and 6 which show the forward section of the machine, there are a pair of rotary dies or swages Ill and I I, each made in two pairs and clamped upon and keyed to a driving shaft, the two shafts I} and I3 being geared together and driven by a suitable motor (not shown). Upon the lower shaft I3 is a crank arm I4 with a crank pin I5 of adjustable throw therein. A-connecting rod IG upon said crank pin is coupled to the fulcrum of a bell crank lever ill (see Figures 2, 5 and '7). The said fulcrum pin has two slides l9, one .at each end of the pin, which run in straight slots '20 in v a frame 2| connected to the machine base a.

There are two rollers 22 on one end of the bell crank lever l8, which run in cam slots 23 in the frame 2|. The other end of the bell crank lever has a connecting rod 24 pivoted thereto, the said rod serving to reciprocate the rod iwhich is carried in brackets along one side of the machine base and which as already described traverses the slide b, to which the ends of the mandrel e and feed screw 0 are secured. If the connecting rod 16 were connected directly to the rod 1', the linear motion of the slide b, mandrel e and feed screw 0 would tend to be different from the linear motion of the tube being swaged when ,the swages were driving the tube backwards towards the slide bduring the actual swaging period, due to the varying angularity of the crank arm l4 as'will be readily understood, but by interposing the bell crank lever l8, the cam track 23 and the connecting rod 24 between the rod l6 and the rod 2', it is possible to compensate for the varyingangularity of the crank arm [4 and to give to the slide 1) a motion substantially the same as the motion imparted to the tube by the swages as they roll thereon during swaging. It is however impossible to effect in a practical manner a correct compensation if the swages operate through an angle of more than about 120 so the swages as shown in Figure 10 are designed to operate'upon the tube for an angular movement of the swages of about 120; the remaining part of the surface of the swages is clear of the tube. The crank arm I4 is so situated with relation to the leading edge of the swage which first engages the tube that it is approximately 30 from the horizontal plane containing .the axis of the bottom swage and the path through which the axis of the fulcrum pin l1 travels in its slot 20. This disposition of the crank arm l4 provides that the compensation to be effected by the cam groove or slot 23 is a minimum as only. the'flatter. part of the circle of movement of the crank pin l5 has to be dealt with.

The rod 1' also reciprocates a slide 25 (see Figures 3 and 6) situated at the delivery side of the dies or swages, which carries a collet or chuck 26. The latter is opened and closed upon the tube coming from the dies or swages by an inertia slide 21 which is coupled by links 28 to levers 29 operating the chuck jaws. The collet or chuck is adapted to be turned by gear wheels 30. 3|, the latter of which is splined or feather keyed upon the screw 32 which is turned by a nut 33, the exterior of which constitutes a ratchet wheel and is held against turning in one direc-.

tion by pawls (not shown). It will be seen therefore that as the slide 25 reciprocates, the collet or chuck 26 will be turned when the slide .moves in one direction, which is to the right in the figures and does not turn when the slide moves in the other direction, that is to the left in the figures.

The inertia slide 21 acts as follows:When the slide 25 moves to the right in Figure 3,,the slide 21 lags and so causes the links 28 to turn the levers 29 and ,close the chuck jaws upon the tube within the chuck. The two slides then move together carrying the tube with them.

' When the slide 25 moves to the left, the slide 21 they release the chuck jaws.

lags and this time turns the levers 29 so that The two slides then move together. The'chuck 26 serves to draw the and the tube end is gripped in the chuck q. The

mandrel end comes between the swages as shown in Figures 3 and 10 at the start of each swaging stroke, the mandrel retreating during swaging due to the crank arm l4, crank pin l5, connecting rod l6, bell crank lever I1, connecting rod 24 and rod i which cause reciprocation of the slide b. 0n the forward stroke of the rod 1', the mandrel e and tube s are turned through an angle which may be 90 by the action of the feed screw c which is turned by the ratchet wheel 12 and so imparts in addition to the reciprocatory movement a feed or forward motion to the'slide r and so to the tube s. The latter enters between the swages and is alternately swaged and released. When released it is fed forward and turned, the mandrel however always reciprocating between the same limits and being turnedon the forward stroke. In other words the tube gradually progresses 'over the mandrel. When the feed screw is moving in a backward direction, the ratchet wheel p turns with it so that the screw has no rotary motion. The tube end progresses towards and is finally engaged by the chuck 25 on its forward stroke until it has all been swaged down and leaves the swages. When one tube has been swaged for the major portionof its length, its end is released from the chuck q and a further tube is fed along the mandrel and its outer end gripped in the chuck q. The latter is fed backwards along the machine base by rotating the motor m and freeing the ratchet wheel p. The motor can also be operated to feed the chuck q to a position in which the tube is about to enter between the swages.

By reference to Figure 10, it will be seen that the swages which turn continuously in one direction, have a portion of their surface covering an angle of about which performs the actual swaging and that whilst swaging is taking place the crank arm I4 is moving through an angle of 120 disposed equally at the opposite sides of a vertical plane containing the axis of the swages. Whenv the swages are engaging the tube, they tend to push it back towards the feed end, and extrude the displaced metal forward towards the delivery end of the machine. of the swages might be utilized to drive the slides backwards, the rod i merely performing the forward propulsion, in which case the co-operating means (namely the bell crank lever l8 and asso- This action ciated'parts) might be dispensed with, the rod i engaging the slides b and 25. at one side only.

The positions of the slides 2'and 25 can be adjusted with relation to the rod i by the nuts shown.

What I claim is:-

1. In a tube rolling mill, incombination, 9)

base or bed, a slide movable along said bed, a chuck upon said slide to receive a mandrel, a

feed screw secured to said slide, a second slide, L75

and imparts a feed movement to the second slide,-

a head containing two rotary swages, a third slide with a chuck thereon at the delivery side of the swages to engage the reduced tube, means for turning said chuck in unison with the other chucks, means actuated in unison with the swages for reciprocating the three slides through definite distances, and means whereby the chuck upon the third slide closeswhen that slide moves in a forward direction and opens when it moves in a reverse direction.

2. In the means claimed in claim 1, a crank arm rotated with one of the swages, a crank pin upon said arm, a connecting rod upon said pin, a bell crank lever, the iulcrum pin of which moves in a straight path and is coupled to the connecting rod, a cam track or groove turn the bell crank lever about its fulcrum as,;it is reciprocated by said connecting rod, a second connecting rod coupled to the bell crank lever,

and a rod reciprocating the three slides coupled to said second connecting rod.

3. In the means claimed in claim 1, two swages having each a swaging surface covering an angle of about 120, a crank arm rotated in unison with one swage and being at an angle of 30 in the rear of the leading edge of the said swage, and means compensating ior the varying angularity oi the crank arm in transmitting reciprocatory motion to the slides.

4. In a tube rolling mill, in combination, a pair of swages'rotating continuously in one direction only, a mandrel reciprocated from and to a definite point in relation to the swages, means for reciprocating the tube being swaged through the same length of traverse as the mandrel upon which it is placed, means imparting increments oi feed to the tube after each swaging operation as the tube moves towards the swages, and means turning both the tubeand the mandrel after each swaging operation as the tube and mandrel move towards the swages.

5. In a tube, rolling mill as claimed in claim 4, providing the swages with a swaging surface extending around not more than 120 only of each swage.

6. In a tube rolling mill as claimed in claim 4, means permitting movements of the tube and mandrel during the swaging operation under the action oi. the swages relatively to the means which impart back or forth or reciprocatory movements to the tube and mandrel.

7. In a tube rolling mill as claimed in claim 1,

means allowing of a limited amount of relative movement between the mandrel and its chuck or chuck slide, means allowing of a limited amount 01' relative movement between the tube and its chuck slide and means reciprocating the mandrel slide through a definite path-in unison with the swages. 

